The invention relates to the protection of information and secret processes stored by electronic means against unauthorized access.
Point of sale terminals (POS, PDV, Pinpad, encrypted keyboard) allow clients to pay their bills using several payment methods, such as credit cards, debit cards, and smart cards. To ensure that payment information is not intercepted from a sales point terminal to a payment center, such information is normally encrypted and protected during transmission, through the use of, for example, digital authentication technology. However, confidential payment information keyed in by the user at a Point of Sale terminal could be intercepted by a physical violation of the Point of Sale terminal. To impede any violation and consequent digital information interception, the keyboard in question is assembled in such a way as to guarantee the inviolability of its internal content, setting off an intruder alarm. The intruder alarm may be triggered by front, rear or side manipulation, or by mechanical perforation of any internal part of the keyboard or of the circuits activated by its keys.
Said intrusion alarm sets off a security mechanism which destroys stored information. Most solutions currently employed do not have a security mechanism for the detection of intrusion circuits inserted in the keyboard. The security mechanism is based on circuits mounted externally on the printed circuit board where the keyboard buttons are to be operated, thereby closing the exposed terminals.
The standard activating mechanism of a keyboard system consists of a rigid printed circuit board containing a demarcated area and two open and exposed terminals connected to an electronic circuit, which in turn detects the closure of these contacts. Each keyboard is connected to a conducting element in the face around the contacts in such a way that, when the keys are pressed, the conducting element touches the two contacts, thereby closing them in a circuit and allowing the keyboard processor to decode any key operated.
An observed disadvantage in conventional solutions is that they allow for the introduction of a device between the circuit board and the keyboard button that would detect the pressing sequence of the keys, and allowing the capture of personal identity numbers (PIN) and other secret information of the user.
One of the objectives of this invention is to provide a constructive device for a keyboard in order to impede the insertion of unauthorized access devices into their internal circuits, ensuring the internal inviolability of installed equipment at the point of sale terminal and increasing the security of keyboard systems.